Magic Lantern is an open-source firmware add-on that works on top of Canon’s DSLR firmware to provide professional video features that were lacking in the early video-capable Canon DSLR. Magic Lantern creators attempted to port the latest Linux kernel version 3.19 to Canon EOS DSLRs, despite the fact that the team has nearly zero experience with kernel development. The hack is best explained by its developers in a quick proof of concept (POC) video below. The next step is to build the userspace binaries such as Graphical User Interface (GUI) and more.
Source: https://thehackernews.com/2015/04/linux-canon-dslr-camera.html